Here at Hercules Propellers, we believe in our products. In aviation structural strength is everything, and unknowns simply aren’t acceptable.
At Hercules we take the structural integrity of our propellers very seriously. When designing a propeller, calculations are made to ensure the propeller is strong and rigid enough to withstand the intended engine RPM, with a large safety margin. Wood being an organic material can vary in quality so we have to make sure the materials we use meet to the minimum strength expectations for the species.
In keeping with Hercules’ toolmaking skills, we have designed and and built apparatus to measure brittleness, Young’s modulus (resistance to bending) and modulus of rupture (ultimate strength) of any given wood sample. Moisture content and density is also an important consideration when selecting timber for propellers and these values are also measured.
Having the apparatus and skills to test the mechanical properties of different wood species, we offer a material testing service to measure the strength of wood samples for aircraft engineers, builders and restorers.
The beam testing press measures how much force is needed to bend a sample by a given distance (Young’s modulus) and also how much force is needed to break the sample (ultimate strength).
The Izod machine has a swinging pendulum which breaks the wood sample. The energy taken to break the sample is measures enabling us to calculte the brittleness.